var canvas = document.getElementById("canvas");
var context = canvas.getContext("2d");


//判断设备
if(IsPC()){
	canvas.width = 320;
	canvas.height = 568;

}else{
	canvas.width = document.documentElement.clientWidth || document.body.clientWidth;
	canvas.height = document.documentElement.clientHeight || document.body.clientHeight;
}
